FAQs on Alexandrite Durability

Definition of Durability in Gemstones

• Overall Meaning: In gemology, durability refers to a gemstone’s ability to withstand wear, heat, light, chemicals, and other potential damages over time. It’s an indicator of how well a gemstone can maintain its appearance and structural integrity under normal to harsh conditions.

Durability of Alexandrite

• Hardness: Alexandrite is relatively hard, scoring 8.5 on the Mohs scale. This means it has excellent resistance to being scratched or abraded, making it suitable for everyday wear in various types of jewelry settings.
• Toughness: Toughness relates to a gemstone’s ability to resist breaking, chipping, or cracking. Alexandrite has fair to good toughness, which means it’s generally durable but can be susceptible to sharp blows or extreme pressure. The toughness of Alexandrite is influenced by its internal structure and any inherent flaws or inclusions it might have.
• Stability: Alexandrite’s stability refers to its ability to withstand exposure to light, chemicals, and temperature changes. It is relatively stable but should be protected from harsh chemicals and extreme temperature variations to prevent possible damage.

Implications of Durability for Owners

Jewelry Design and Use: The high hardness and good toughness of Alexandrite make it a versatile choice for various jewelry designs, including rings, earrings, and necklaces. However, due to its susceptibility to hard knocks, designs that offer some protection, like bezel settings, may be advantageous.

Care and Maintenance: Owners should clean Alexandrite gently using mild soap and water, avoid exposing it to harsh chemicals, and protect it from extreme temperatures. It’s also wise to store Alexandrite jewelry separately to prevent scratches from harder materials.

Lifestyle Considerations: For those leading an active lifestyle or working in environments where the gemstone might be exposed to rough conditions, extra caution is advised when wearing Alexandrite jewelry.

Hardness: The Mohs Scale

Mohs Scale of Hardness: The primary tool for measuring the hardness of Alexandrite is the Mohs Scale. Alexandrite ranks at 8.5 on this scale, which ranges from 1 (softest) to 10 (hardest). This scale assesses a gemstone’s ability to resist scratches and abrasions.

Implication of Hardness: With a rating of 8.5, Alexandrite is quite resistant to scratches, comparable to other hard gemstones like topaz. This high rating implies that Alexandrite can withstand daily wear and tear, making it suitable for everyday jewelry.

Toughness: Resistance to Breaking and Chipping

Assessing Toughness: Toughness in gemstones refers to their ability to resist breaking, chipping, or cracking. Unlike hardness, there isn’t a standardized scale for measuring toughness. Instead, it is usually categorized descriptively, from excellent to poor.

Alexandrite’s Toughness: Alexandrite has fair to good toughness, which means it is relatively resistant to impacts and mechanical stress. However, it can still be vulnerable to sharp blows, especially along cleavage planes or at exposed points in certain cuts.

Stability: Reaction to Environmental Factors

Evaluating Stability: Stability in gemstones like Alexandrite concerns how well they resist changes or damage due to environmental factors such as heat, light, and chemicals.

Alexandrite’s Stability: Alexandrite is generally sensitive to light and common chemicals, but it can be sensitive to extreme heat or sudden temperature changes. Prolonged exposure to harsh chemicals should also be avoided to maintain its integrity.

Practical Implications for Alexandrite Owners

Alexandrite’s Hardness

Alexandrite’s Toughness

Toughness, on the other hand, refers to a gemstone’s ability to resist breaking, chipping, or cracking when subjected to impact or stress. It’s about the gemstone’s structural integrity.

Factors Affecting Toughness: Unlike hardness, toughness is influenced by a gemstone’s overall structure, its internal inclusions, and sometimes by the way it’s cut. These can create points of weakness where the gemstone is more susceptible to damage.

Alexandrite’s Toughness: While Alexandrite has good toughness, it’s not impervious to breaking or chipping. It’s more vulnerable to damage from sharp blows, pressure, or extreme stress, especially along any natural lines of weakness in the crystal.

Factors Influencing Alexandrite’s Durability

Geological Origin: Alexandrite’s durability can be influenced by its place of origin. Different geological settings can impact the gemstone’s internal structure, affecting its toughness and overall durability.

Natural vs. Synthetic Varieties: Generally, natural Alexandrite is more durable compared to synthetic counterparts. The natural formation process contributes to its inherent toughness and resistance to wear and tear.

Clarity and Inclusions: The presence and nature of inclusions within Alexandrite can affect its durability. Stones with fewer or no inclusions typically exhibit better toughness and are less prone to cracking or chipping.

Alexandrite Varieties Known for Exceptional Durability

Ural Mountains Alexandrite: The original and historically most prized Alexandrite comes from Russia’s Ural Mountains. These stones are not only famous for their dramatic color change but are also known for exceptional durability. Their formation under unique geological conditions contributes to their robustness.

Brazilian Alexandrite: Alexandrite sourced from Brazil is also known for its impressive durability. Brazilian varieties often exhibit a strong structure, making them resistant to scratches and capable of withstanding everyday wear.

Sri Lankan Alexandrite: While slightly softer than their Ural and Brazilian counterparts, Alexandrites from Sri Lanka can still possess good durability. They are generally well-suited for jewelry but may require slightly more care.

What are the Inclusions in Alexandrite?

Nature of Inclusions: Inclusions in Alexandrite are internal features that can be minerals, fractures, or even cavities. They are natural occurrences that can vary in size, number, and type, depending on the gemstone’s formation process.

Types of Inclusions: Common inclusions in Alexandrite might include crystals of other minerals, fluid inclusions, or tiny fissures. These are often microscopic and may require magnification to be seen.

Impact of Inclusions on Durability

Weakening of Structure: Inclusions can create weak points within the Alexandrite. These areas are more susceptible to damage, such as cracking or breaking, especially under stress or impact.

Fracture-Filled Inclusions: Some Alexandrites may have fractures that are filled as a form of enhancement. While these fillings can improve appearance, they may also affect the stone’s resistance to heat and pressure during repairs or setting in jewelry.

Type and Location Matter: The impact of inclusion on Alexandrite’s durability greatly depends on its type and location. Large or numerous inclusions, especially those near the surface, can significantly weaken the gemstone.

Alexandrite’s Hardness and Toughness

• Hardness: Alexandrite ranks high on the Mohs scale of hardness, meaning it’s resistant to scratches. However, hardness does not directly correlate to toughness.
• Toughness and Inclusions: The toughness of Alexandrite, its ability to resist breaking or chipping, can be compromised by inclusions. A stone with fewer or smaller inclusions generally has better toughness.

Practical Implications for Owners and Buyers

Careful Selection: When purchasing Alexandrite, consider the type and extent of inclusions. Opt for stones that strike a balance between aesthetic appeal and structural integrity.

Handling and Maintenance: Alexandrite with significant inclusions should be handled more carefully. Avoid exposure to harsh conditions, and be mindful during cleaning and storage.

Professional Advice: When setting Alexandrite in jewelry, seek professional advice. Jewelers can recommend settings that protect the stone, especially if it has notable inclusions.

Regular Inspections: Periodic check-ups by a professional jeweler are recommended to ensure the gemstone remains secure in its setting and to check for any damage.

Types of Treatments for Alexandrite

Impact of Treatments on Durability

Stability and Hardness: Treatments like heat may slightly alter the stability of Alexandrite but generally don’t significantly change its hardness. Alexandrite’s natural hardness (8.5 on the Mohs scale) remains its primary defense against scratches and abrasions.

Vulnerability to Damage: Treated Alexandrites, especially those with fracture fillings, may require more careful handling. They can be more susceptible to damage from harsh chemicals, heat, and physical impacts.

Longevity of Treatments: Some treatments may not be permanent and can deteriorate over time, especially under exposure to harsh environmental conditions, potentially affecting the gemstone’s appearance and necessitating re-treatment.

Best Practices for Treated Alexandrite

Informed Purchasing: When buying Alexandrite, inquire about any treatments it may have undergone. Understanding these can help gauge how the gemstone will hold up over time.

Care and Maintenance: Treated Alexandrite should be carefully maintained. Avoid exposure to high heat, harsh chemicals, and extreme pressure. Regular cleaning with mild soap and water is recommended.

Professional Inspection: For jewelry pieces, periodic professional inspections are advisable to ensure the setting remains secure and to check the condition of the gemstone, especially if it has been treated.

Suitability of Alexandrite for Daily Wear

Hardness and Resistance: Alexandrite has a high level of hardness, rating 8.5 on the Mohs scale. This makes it resistant to scratches and abrasions, which are common concerns in daily wear.

Durability Concerns: Despite its hardness, Alexandrite is not impervious to all types of damage. It has fair to good toughness, which means it can withstand minor knocks and bumps but may be susceptible to chipping or breaking if subjected to harsh impacts.

Precautions for Daily Wear

Avoiding Harsh Physical Activities: While engaging in activities that involve physical labor, sports, or the use of heavy machinery, it’s advisable to remove Alexandrite jewelry. This prevents potential impacts that could cause chipping or dislodging of the stone.

Protection from Chemicals: Exposure to harsh chemicals, including household cleaners and chlorine in swimming pools, can damage Alexandrite. It’s best to remove the jewelry when handling such substances.

Care in Extreme Temperatures: Sudden temperature changes can affect Alexandrite. Avoid wearing it in situations where it might be exposed to extreme heat or cold, such as in saunas or during outdoor winter activities.

Safe Storage: When not wearing your Alexandrite jewelry, store it in a fabric-lined jewelry box or a soft pouch. Keeping it separate from other jewelry prevents scratches and accidental impacts.

Cleaning and Maintenance

Regular Cleaning: Clean Alexandrite with a soft brush, lukewarm water, and mild soap. Rinse thoroughly and dry with a soft, lint-free cloth.

Professional Check-ups: Regular inspections by a professional jeweler are recommended to ensure the settings are secure and to identify any potential issues early on, especially for pieces worn daily.

Understanding Wear and Tear

Natural Aging: Over time, all jewelry shows signs of wear. Regular maintenance and careful handling can minimize these effects and prolong the life and beauty of Alexandrite jewelry.

Insurance Consideration: For valuable Alexandrite pieces, consider insurance to protect against loss, theft, or accidental damage.

Alexandrite’s Hardness and Scratch Resistance

Mohs Scale Rating: Alexandrite ranks high on the Mohs scale of hardness, scoring 8.5 out of 10. This places it among the harder gemstones, making it relatively resistant to scratches under normal wear conditions.

Scratch Resistance: Due to its hardness, Alexandrite is less likely to get scratched by materials that are lower on the Mohs scale. This includes common substances one might encounter in daily life, like metal or dust particles.

Factors Influencing Chipping in Alexandrite

Toughness: While Alexandrite is hard, its toughness – the ability to resist breaking or chipping – is not as high as its hardness. The gemstone’s internal structure and the presence of natural inclusions or flaws can impact its toughness.

Type and Location of Inclusions: Alexandrite with significant inclusions, especially near the surface or along the edges, may be more susceptible to chipping. Inclusions can create weak points in the gemstone where it’s more likely to break under impact.

Cut and Faceting: The way Alexandrite is cut and faceted can also influence its vulnerability to chipping. Certain cuts with more exposed edges or points, like marquise or pear shapes, might be more prone to chipping compared to rounded or protected cuts.

Variations Among Alexandrite Stones

Natural vs. Synthetic: Natural Alexandrite may have a range of inclusions that affect its susceptibility to damage, whereas synthetic Alexandrite typically has fewer inclusions, potentially making it less prone to chipping.

Source and Quality: The source of Alexandrite can play a role in its overall quality and structural integrity. High-quality stones, carefully extracted and processed, generally have fewer weaknesses that could lead to chipping or scratching.

Precautions and Care

Careful Handling: Alexandrite jewelry should be worn and handled with care, especially when engaging in activities that could expose it to hard knocks.

Appropriate Settings: Choosing protective settings for Alexandrite jewelry, such as bezel settings, can help shield the stone from impacts.

Regular Inspections: Frequent checks by a professional jeweler can help spot any potential issues with the gemstone or the setting, preventing further damage.

Basic Guidelines for Cleaning Alexandrite

Gentle Cleaning Solution: Use a mild soap and lukewarm water to create a cleaning solution. Harsh chemicals and abrasive cleaners should be avoided as they can damage the Alexandrite or alter its appearance.

Soft Brush for Cleaning: Utilize a soft-bristled brush, such as a toothbrush, to gently clean the Alexandrite. This helps remove accumulated dirt and oils, especially in hard-to-reach areas like under the gemstone in a ring setting.

Rinsing and Drying: Thoroughly rinse the Alexandrite under lukewarm running water after cleaning. Be sure to close the sink drain or clean over a bowl to prevent accidental loss. Dry the gemstone and set with a soft, lint-free cloth.

Special Considerations for Alexandrite

Ultrasonic and Steam Cleaners: Generally, ultrasonic cleaners are not recommended for Alexandrite, especially if the stone has inclusions or has been fracture-filled. Steam cleaners should also be avoided, as Alexandrite can be sensitive to sudden temperature changes.

Temperature Sensitivity: Alexandrite should not be exposed to extreme temperatures during cleaning. Sudden temperature shifts can cause damage, especially if the gemstone has any existing fractures or weaknesses.

Handling Inclusions: If your Alexandrite has visible inclusions, extra care should be taken during cleaning. Aggressive scrubbing or harsh chemicals can exacerbate these inclusions, potentially leading to damage.

Regular Maintenance and Care

Regular Inspections: Have your Alexandrite jewelry inspected regularly by a professional jeweler. This ensures that the settings are secure and can identify any potential issues before they become problematic.

Careful Wearing: While Alexandrite is relatively durable, it should be protected from hard impacts and exposure to harsh chemicals. Consider removing Alexandrite jewelry during activities like gardening, cleaning, or sports.

Proper Storage: Store Alexandrite jewelry separately from other pieces to avoid scratches. A fabric-lined jewelry box or a pouch is ideal.

Alexandrite and Temperature Sensitivity

Thermal Shock Risk: Alexandrite, like many gemstones, can be susceptible to thermal shock. Sudden and extreme temperature changes can cause stress within the stone, potentially leading to cracks or fractures, especially if the Alexandrite already contains natural inclusions or fissures.

Heat Exposure: Prolonged exposure to high temperatures may not only risk thermal shock but can also potentially alter some of the internal characteristics of Alexandrite. While this is a relatively rare occurrence, it’s a risk worth considering for the preservation of the stone.

Precautionary Measures: To mitigate these risks, avoid wearing Alexandrite jewelry in environments where rapid temperature changes can occur, such as saunas, hot tubs, or very cold environments. When storing, keep the stone at a stable temperature.

Effects of Sunlight Exposure

Color Stability: One of Alexandrite’s most prized attributes is its color-changing property. Fortunately, Alexandrite is generally stable under exposure to sunlight, with no significant risk of color fading. This robustness to light exposure is a distinct advantage for a gemstone often admired for its visual properties.

Prolonged Sunlight Exposure: Although unlikely to affect the color change, prolonged and intense sunlight exposure should still be avoided as a precautionary measure to maintain the overall integrity of the stone.

Maintaining Alexandrite’s Durability

Cautious Wearing: When wearing Alexandrite, consider the day’s activities and environments to minimize risk from temperature fluctuations or excessive sunlight.

Regular Checks: Periodic checks by a professional jeweler can help identify any potential damage or weaknesses, particularly if the stone has been exposed to harsh conditions.

Storage and Care: Store Alexandrite in a cool, shaded place, away from direct sunlight and sources of extreme heat or cold. A fabric-lined jewelry box or a pouch is ideal for storage.